Risk in a Hypermobile World

A recent BBC radio 4 programme entitled Thinking Streets takes listeners on a refreshing tour of traffic management schemes that are elevating the status of pedestrians and cyclists relative to that of those in motor vehicles. The effect, as researcher/presenter, Angela Saini notes, is civilizing – while also reducing accidents. The programme features Ben Hamilton-Baillie, who it rightly describes as Britain’s “biggest advocate of shared space”. He is also a very convincing advocate with a website worth visiting. I have a brief part in the programme explaining the concept of risk compensation.

Traditional highway engineering assumes that safety requires the spatial segregation of pedestrians, cyclists and motorized vehicles or, where this is not possible, rigorously enforced rules, signs and signals dictating temporal segregation. Road users, according to the established paradigm, are irresponsible, stupid, selfish automatons whose safety can only be assured by physical barriers to conflict, supplemented by legal sanctions for disobeying the rules.

“Shared space” stands many of the traditional assumptions on their heads. It assumes a very different road user ‐ one who is responsible, alert and responsive to evidence of safety or danger. It proposes tearing down physical barriers such as pedestrian guard rails and segregation infrastructure such as pedestrian bridges, and filling in pedestrian tunnels. It also proposes removing stop signs and traffic lights and other signage and road markings demanding compliance at the cost of criminal or financial sanctions. It deliberately creates uncertainty as to who has the right of way on the assumption that road users will work it out for themselves in a civilized fashion.

Anthony Cartmell says:

January 9, 2012 at 8:52 pm (UTC 0)

Shared space works very well, so long as you don’t allow the bullies (usually people in motor vehicles when looking at streets) to dominate the place. Sadly “shared space” in the UK often just means removing signs and kerbs, without making any changes to relative risks for different groups of road user. For example: Exhibition Road, London, an ineffective un-shared space.

From a risk compensation point of view, a car driver suffers from very little risk of being hurt if they accidentally collide with a pedestrian, while a pedestrian suffers a great risk of being hurt in a collision with a car. Thus the pedestrian naturally takes a lot more care than the car driver does, and the car driver always wins the game of “chicken” when negotiating who should give way to whom.

Looking at this another way, “shared space” works when the apparent risks to all road users are balanced. Just removing signs and kerbs, in the hope that everyone will suddenly take turns because the boundaries have gone, is trying to change an effect without affecting the root cause.

If you want the motorists to share, you have to make them feel as vulnerable as the cyclists and pedestrians, and that’s not easy to achieve. This can be done, though, by making the motorist feel as though they’re a tiny minority. Or you can make the motorist realise that they’re about to become vulnerable pedestrians themselves, as in large car parks.

In my experience, shared space works between cyclists and pedestrians much better than between cars and pedestrians or between cars and cyclists. In a cyclist+pedestrian space, the risks are much more evenly balanced than when there are motor vehicles present, so cyclists (the more dangerous mode) do moderate their behaviour significantly.